Electric gas lighting devices are known which are used for producing sparks to light burners on gas cooker ranges, and which normally comprise an ignition circuit fitted underneath the cooking range and for generating sparks, and one or more switches operated manually to activate the ignition circuit.
More specifically, the ignition circuit is connected to a supply line having a neutral line and a phase line and supplying alternating supply voltage, and comprises two enabling terminals, one of which is connected to the neutral line. Alternatively, the mains may be used to drive the charge circuit.
The normally-open hand-operated switches are connected in parallel between the enabling terminals of the ignition circuit, and, being operated manually by the user, are formed on a flame regulating panel of the cooking range.
A drawback of known gas lighting devices of this type lies in the hand-operated switches being located some distance from the ignition circuit, so that two conducting wires, for electrical connection and return, must be routed to each, thus making them bulky and expensive to install.
To overcome the above drawback, the Applicant's co-pending Italian Patent Application MI2000A002814 proposes using a single-wire control catenary, with return via the cooking range made of appropriately earthed conducting material. Such a solution, however, cannot be applied in the case of mains-driven charge circuits, by being electrically unsafe. What is more, when applied (as in the above patent application), it calls for relatively complex, high-cost ignition circuits with appropriate radio noise filters.